Elle Fielding has taken the literary world by storm, with her first book hitting the bestsellers lists and making big money. But now she's under pressure from her publisher to produce a follow-up that's just as compelling. Having spent a chunk of her earnings remodelling her dream house on the cliffs, she decides to take a break to try to cure her writer's block, renting the property out on Airbnb while she's away. Upon her return, however, she realises something has changed. Despite her friends' reassurances that everything is fine, and her vivid imagination must be running away with her, Elle is increasingly convinced something is seriously wrong. As fear and paranoia close in, her own home becomes a prison. Someone is unlocking her past - and she's given them the key...